Electromagnetic operators



Jan. 5, 1965 J. v. FOSTER 3,164,757

ELECTROMAGNETIC OPERATORS Filed Dec. 12, 1961 uE on nao n 34 2O 9 32 #27 5 2| 40 *26 FIE? l4 l2 u as FIG.6.

FIG

JACK V. FOSTER United States Patent 3,164,757 ELECTRUMAGNETKC @PERATGRS iacit V. Foster, Fort liranch, Ind, assignor to American This invention relates to electromagnetically powered operators and, more particularly, to such operators which include two alternatively energized electromagnetic motor devices in combination with automatic latching means. The present invention provides advantageous improvements in'operators of the kind employed in that general type of relay disclosed in United States Patent 2,819,364, issued January 7, 1958, to J. H. Jaidinger.

In the type of relay referred to, the two electromagnetic motor devices are secured to a common base in end-to-end relation with theirpivoted armatures adjacent to each other, the armatures being arranged to pivot about parallel axes. Each motor device includes a biasingspring which serves to pivot the armature away from the electromagnet of the motor device and toward the other armature when the motor device is not energized. On each armature there is mounted a latch member, the two latch members cooperating in such fashion that, once one of the motor devices has been energized to pivot its armature against the biasing action of the associated spring, the other armature moves, under thebias applied by its spring, into a position such that the latch members hold the just energized motor device in its actuated position after deenergization of the electromagnet.

While thistype of relay has received extensive commercial acceptance, it has heretofore had a maximum operating life which, at most, would extend for perhaps 500,000 cycles of operation. There has been an active demand for relays of this type which would have a satisfactory operating life on the order of at least several million cycles of operation.

The present invention is based in part upon the observation that the factor which limits the operating life of such latching relays is a change in the surface characteristics of those portions of the latch members which ride on and engage each other to accomplish the latching operation. As heretofore manufactured, the latch members of such relays have been formed of metal strips, usually chrome-plated to resist wear. During extended operation, the plating is gradually destroyed on the working surfaces of the latch members and these surfaces become scored or galled. As such damage to the working surfaces of the latch members develops, the frictional forces involved in engagement between the latch members increase, eventually becoming so great that the motor devices no longer have adequate power to operate the relay eifectively. Thus, in effect, the operating life of the relay depends primarily upon the ability of the working surfaces of the latch members to survive many cycles of operation.

A general object of the present invention is toprovide .a latching operator of the type described which embodies novel latch members so constructed and arranged as to be capable of survivingat least several times the number of cyclesof operation that has heretofore been considered to be the practical upper limit for such 1 operators.

Another object is to provide an operator of this type wherein the latch members operate with greater effectiveness and dependability than has heretofore been possible.

3,164,757 Fatented Jan. 5, 1965 In order that the manner in which these and other objects are attained in accordance with the invention can be understood in detail, reference is bad to the accompanying drawings, Which form a part of this specification, and wherein:

FIG. 1 is a side elevational view of a latching relay constructed in accordance with one embodiment of the invention, and illustrating the relay in one of its two actuated conditions;

FIG. 2 is a plan view, with parts removed for clarity of the relay of FIG. 1;

FIG. 3 is a perspective view of one of the latching members of the relay of FIG. 1;

FIG. 4 is a perspective view of the other of the latching members of the relay of FIG. 1;

FIG. 5 is a fragmentary side elevational view of a portion of the relay of FIG. 1, in the other of its actuated conditions; and p FIG. 6 is aside elevational view of a latching relay constructed in accordance with a second embodiment of the invention.

Turning now to the drawings in detail, and first to FIGS. 1-5 thereof, it will be seen that the embodiment of the invention here illustrated comprises a base '1 on which are mounted two electromagnetic motor devices indicated generally at 2 and 3.

Motor device 2 includes a U-shaped frame 4 which is fixedly attached to base Iby a pair of screws and spacers indicated at 5, one of the parallel legs 6 of the U-shaped frame extending parallel to and being spaced somewhat above base 1, as shown. Fixedly secured to the base 7 of the U-shaped frame 4 is a conventional A.C. electromagnet 8, the axis of the electrom-agnet being parallel to base 1 and the pole face thereof being exposed as indicated at 9. A fiat magnetic armature 10 is pivoted on the tip of frame leg 6 in any suitable fashion, the Qend of leg 6 presenting a bearing edge which defines the pivotal axis-for the armature. Fixed to the lower face of frame leg 6 is a combined armature retaining member and biasing spring mount 11. At its end adjacentthe armature, member 11 is provided with an opening, and the armature has a tab 12 extending through the opening. At its opposite end, member 1-1 is pro vided with a spring retaining tab 13. A helical tension spring 14 has its ends engaged respectively about tabs 12 and 13, the spring being maintained in tension so as to bias armature 10 pivotally away from pole face 9.

Mounted on the upper leg 15 of the U-shaped frame 4 is the fixed contact assembly indicated generally at 16. Assembly 16 includes an integrally molded insulating body 17 in which are embedded contacts 18 and 19, the contacts 18 and 19 projecting toward the axis of electromagnet 8 and being spaced apart axially of the electromagnet, as shown. Contacts 18 and 19 constitute one pair of fixed contacts, and it will be understood that the asembly 16 can involve a number of such pairs of contacts in the usual fashion.

Rigidly mounted on armature 10, as by screws 20, is an assembly comprising an insulating sheet 21, a molded integral body of insulating material 22, and a latch member 23. therein at least one spring contact arm 24, arm 24 projecting laterally of electromagnet 8 to terminate between fixed contacts 18 and 19. t

it will be understood that, when electromagnet 8 is energized, its magnetic effect causes armature it to pivot into contact with the exposed pole face 9, against the biasing action of spring 154, bringing the contact carried by arm 24 into engagement with fixed contact 18. When electromagnet d is deenergized, spring 14- biases the armature 10 to pivot in the opposite direction. However, due to the latch mechanism, which will be described subse- Insulating body 22 has embedded v3 quently, the armature 1ft does not pivot in the opposite direction. Hence, the contact carried by the tip of arm 24 remains in engagement with fixed contact 18 and does not return to its original position when the electromagnet is deenergized, until the latch mechanism is operated. Absent the latch mechanism, the armature 1t and contact arm 24 would naturally pivot away from electromagnet 8 under the action of spring 14 when the electromagnet is deenergized.

Electromagnetic motor device 3 is identical to device 2 and includes a U-shaped frame 25 mounted on base 1, as by screws and spacers indicated at 26, so that the lower leg 27 of frame 25 extends parallel to base 1 at least substantially in the same plane as leg 6 of frame 4. An electromagnet 23 is fixedly mounted on the base 29 of frame 25, so as to present an exposedpole face St). A magnetic armature 31 is pivotally mounted on lower leg 27 of frame 25, being retained by member 32 in the same manner hereinbefore described with reference to armature 1t) and member 11. Armature 31 is biased away from pole face 3i? by a tension spring 33.

Fixedly mounted on the upper leg $4v of frame 2-5 is a fixed contact assembly 35. Assembly 35 comprises an integral molded body of insulating material 36 and at least a pair of fixed contacts 37 and 38. Fixed contacts 37 and 38 are parallel and project toward the axis of electromagnet 23, being spaced axially with respect to the electromagnet.

Rigidly mounted on armature 31, as by screws 39, is an assembly comprising an insulating sheet 4%, an integrally molded insulating body 41 and latch member 42. Body 41 has embedded therein at least one spring contact arm 43, arm 43 projecting laterally of the electromagnet to terminate between fixed contacts 37 and 38. Thus, when electromagnet 2.8 is energized, so that armature 31 is pivoted into contact with exposed .pole face 39, the contact carried at the tip of arm 43 is brought into engagement with the fixed contact 38. Upon deenergization of electromagnet 255, spring 33 biases the armature to pivot away from pole face 30, so that the contact carried at the tip of arm 43 is brought into engagement with fixed contact 37. Here again, the armature it will not actually pivot until the latch mechanism is operated, as will be described subsequently.

It will be observed that the electromagnetic motor devices 2 and 3 are arranged in end-to-end relationship, with the armatures thereof adjacent each other and with the pivotal axes for the armatures parallel to each other and lying in a common plane parallel to base 1. Thus, latch members 23 and 42 are opposed to each other across the space between the two armatures of the relay assembly.

Latch member 23 consists of a single metal strip, bent intermediate its ends, so that the strip includes a base or mounting portion 44 having openings through which screws 26 pass. The intermediate bend in latch member 23 is disposed well above the common axis of the two electromagnets and is such that a second portion 45 of latch member 23 projects away from armature at an angle of 45. As will be clear from FIG. 3, latch member 23 is generally rectangular in plan, and the edge at the free tip of portion 45 thereof provides a face 46 which is parallel to the pivotal axes of the armature and which is directed generally toward electromagnetic motor device 3. Near end face 46 of portion 45 of latch member 23, the body of the metal strip is lanced and struck up in such fashion as to provide an offset portion which, as seen in FIG. 3, is also of generally rectangular shape. The tip of the lanced portion provides a second face 47 parallel to face 46, both faces 46 and 47 extending transversely of the latch member. Faces 46 and 47 are spaced apart along portion 45 of latch member 23 and can be considered as being interconnected by a longitudinally extending portion 48 of the lower face of portions of the latch member.

stops.

Latch member 23 can be formed of any essentially rigid metal and at least that portion thereof presenting faces 46, 47 and 48 is provided with a tenacious chrome plating to provide bearing surfaces.

In this embodiment, latch member 42 is an integral, molded body of a dimensionally stable synthetic resinous material having antifriction characteristics. Advantageously, latch member 52 is molded or otherwise formed of nylon or equivalent polymeric material. As will be clear from PEG. 4, member 42 is rectangular in front plan and has a rectangular transverse cross section. The main body portion 49 of latch member 42 has flat parallel front and rear faces and is provided with suitable openings to accommodate the mounting screws 39. Front face 5% of member :2 extends as a flat surface for most of the length of the latch member. However, adjacent the end of the body opposite the axis of armature 31, the tip portion of latch member 42 is formed with two transverse projections extending outwardly from front face 50, each 'eing of triangular cross section longitudinally of the body of the latch member. Thus, projection 51, located at the tip of the body, presents faces 52 and 53 which are at right'angles to each other and each of which extends at an angle of with respect tofront face of the latch member. Similarly, projection 54, located immediately adjacent to projection 51, presents faces 55 and 56 which are at right angles to each other and extend at 4 to front face 50. Hence, faces 52. and 55 are transverse, parallel faces spaced apart in the direction of face 53 Thus, faces 52 and 55 of latch member 42 correspond to faces 46 and 47, respectively, of latch member 23, while face 53 of latch member 42 corresponds to face 48 of latch member 23.

Referring again to FIG. 1, it will be noted that the armatures ltl and 31 project upwardly in the same general direction from their parallel pivotal axes and that the faces and 47 of latch member and faces 52 and 55 of latch member 42 are spaced apart, respectively, along lines which extend at 45 to the respective armatures, the two 45-lines along which these pairs of faces are spaced converging toward each other and away from the pivotal axes of the armature. The intermediate, longitudinally extending faces 48 and 53 extend at least generally in the directions in which faces 46, 47 and 52, 55 are respectively spaced. Faces 46 and 52 are both spaced from the planes of their respective armatures by essentially the same distance. Similarly, faces 47 and 55 are both spaced from the planes of their respective armatures by essentially the same distance. Latch members 23 and 42 are so dimensioned, and so mounted on their respective armatures, that the radial distance between face 46 and the pivotal axis of armature 16 is essentially the same as the radial distance between face 52 and the pivotal axis of armature 31. Similarly, the radial distance of face 47 from the pivotal axis of armature 1h is essentially equal to the corresponding radial distance of face 55 from the pivotal axis of armature 31. The spacing between faces 46 and 47 is essentially equal to the spacing between faces 52 and 55. Accordingly, within the limits of pivotal movement allowed the two armatures, a parallelogram relationship is maintained between faces 46, 47, 48, 52, 53 and 55.

When electromagnet 8 of motor device 2 is energized, the resulting pivotal movement of armature 1t causes latch member 23 to swing away from latch member 42. As soon as such swinging movement commences, latch member 42 is caused to follow latch member 23, since biasing spring 33 pivots armature 31 toward motor device 2, it being understood that electromagnet 28 of the motor device 3 is not energized at this time. As a result of energization of electromagnet 8, armature 10 is brought into direct engagement with the exposed pole face 9 of that electromagnet andthe armature accordingly Since latch member 23 is rigidly mounted on 55 armature 10,,latch member 23 thus stops in a predetermined position.

As it follows latch member 23 latch member 42 travels a path such that the outermost face 52 of latch member 42 rides under the tip face 46 of. portion 45 of latch member 23. Hence, face 52 rides along the intermediate face 48 of latch member 23 and the movement of latch member 42 is ultimately stopped by engagement of face 53 with face 47.

When electromagnet 8 is now deenergized, the moving parts of the relay remain in the position seen in FIG. 1, biasing spring 33 holding latch member 42 in the latching engagement with latch member 23 just described. In this position the face 52 of latch member 42 is in engagement with the face 48 of latch member 23 and the armature is prevented from pivoting under the action of the biasing spring 14.

If electromagnet 28 is now energized, armature 31 is pivoted into direct engagement with the exposed pole face 30 of electromagnet 28 and the armature is therefore stopped. Since armature 31 is stopped in a fixed position, latch member 42, rigidly mounted on the armature, is also necessarily stopped in a fixed, predetering engagement of face 46 with face 53, just described,

is preserved.

It is to be noted that, in FIG. 5, as latch member 42 swings away from latch member 23, face 52 slides along face 48. Due to the pressure of face 48 against face 52 caused by the biasing action of spring 14, there is a frictional rubbing or sliding of face 52 against face 48 when latch member 42 is pivoted away from latch member 23. correspondingly, when in the opposite latched position and electromagnet 8 is energized, the surfaces in frictional engagement are faces 46 and 53. As the faces 46, 43, 52 and 53 wear, the coeflicient of friction must not increase radically or a condition will result where the frictional forces are so great that the electromagnets will not pivot the armatures. It has been found that the present coacting latch members do not exhibit marked wear or increase in friction as a result of continued use. I

The relay illustrated in FIGS. 1-5 has proved to have a remarkably long operating life, successful operation through 10 million cycles being readily attainable when latch member 42 is of nylon. Such vastly increased operating life results from the fact that, while retaining adequate strength and dimensional stability, latch member 42 has excellent antifriction characteristics. The chrome-plated faces 46, 47 and 48 of latch member 23 are not galled or otherwise damaged by their contact with the corresponding portions of latch member 42, and the frictional forces involved in the coaction between the two latch members are not only initially minimized but also FIG. 6 illustrates a modifiedform of theinvention wherein one of the latch members 23' is an integral strip of metal and the other latch member 42' is a composite member consisting of a metal strip 60 and a tip 61 formed of nylon or equivalent synthetic resinous antifriction material and rigidly attached to strip 60.-

Tip 61 is essentially the same as the tip of latch member 42 and includes projections 62 and 63 extending transversely of the latch member and of right triangular cross section lengthwise of the latch member. It will be clear from FIG. 6 that projection 62 presents faces corresponding to faces 52 and 53 of projection 51, FIG. 4, while projection 63 presents faces corresponding to faces and 56, FIG. 4. Recognizing that latch member 23 is identical with latch member 23, FIG. 3, and that the relay of FIG. 6 is identical with that of FIG. 1 save for the difference between the latches of the two embodiments, it willbe understood that latch members 23 and 42' coact precisely in the manner hereinbefore described with reference to latch members 23 and 42.

Strip includes aflat mounting portion 64, an offset 65 and a straight end portion 66 parallel to but spaced from portion 64. Tip 61 is molded with end portion 66 embedded therein. The embodiment of FIG. 6 retains the operating characteristics of that of FIGS. 1-5 and has the advantage that both latch members 23 and 42 can be adjusted manually by bending. In this connection, it will be understood that strip 60 can be bent, in the area of offset 65, with relative ease.

While nylon is an advantageous antifriction material from which member 42, FIG. 4, and member'61, FIG. 6, can be formed, other equivalent materials can be em ployed. Thus, any polymeric synthetic resinous material having both dimensional stability and antifriction characteristics is suitable. Alternatively, members 42 and 61 prevented from markedly increasing over prolonged pesembled, to assure proper cooperation between the two latch members.

Provision of secondary faces 47 and 55 prevents over travel of the armatures, both during shipping, for example, and in operation, so minimizing the danger of damage to the contact structures which could otherwise result from physical shock or impact.

two alternately energized motor devices each including an electromagnet;

an armature mounted adjacent the electromagnet for pivotal movement, about an axis transverse to the axis of the electromagnet, toward and away from the electromagnet; and a spring connected to the armature to bias the same away from the electromagnet, the motor devices being mounted on the support in at least generally end-to-end relation with the armatures adjacent each other and the pivotal axes of the armatures in parallel spaced relation to each other, the combination of a pair of latch members each mounted on a different one of the armatures and each extending generally along the length of the armature on which it is mounted and away from the pivotal axis of'the armature, each of said latch members having a tip portion spaced from the pivotal axis of the armature on which such latch member is mounted, said tip portions generally opposing each other across the space between said latch members, each of said tip portions comprisinga pair of transverse faces extending parallel to the pivotal axes of the armatures and spaced apart in a direction extend- 3,16%,757 '2 ing at an oblique angle to the armature on which the said tip portion of synthetic resinous material includes latch member is mounted, the directions of spacing a pair of parallel transverse projections each of triof said pairs of, transverse faces converging toward angular cross section lengthwise of the latch memeach other away from the pivotal axes of the arma her, said projections presenting said pair of faces of tures, the latch member on which they are provided. said tip portions each having a longitudinally extend- 4. An eleetromagnetically powered operator in acing face interconnecting said transverse faces, said cordance with claim 1 and wherein longitudinally extending faces of each of said tip porone of said latch members is an integral body of a syntions being directed toward the other of said tip thetic resinous material having anti-friction properportions, 1O ties. the outermost one of said pair of transverse faces of 5. An electromagnetically powered operator in accordone of said latch members engaging said longitudiance with claim 1 and wherein nally extending face of the other of said latch memsaid tip portion of one of said latch members is a body bers in each actuated condition of the operator, of synthetic resinous material having antifriction said pair of faces and said longitudinally extending properties, and

face of at least one of said latch members being of the other of said latch members is an integral metal antifriction material, strip including a first portion extending generally energization of one of the motor devices causing the along the armature on which said other latch memone of said latch members mounted on the armature her is mounted, and a second portion extending away of that motor device to pivot away from the other 0 from the armature in the direction of the spacing of said latch members, the spring of the other motor etween said transverse faces of said other latch device then causing the armature thereof to pivot member. toward said one latch member, the outermost one 6. An electromagnetically powered operator in accordof said transverse faces of said other latch member ance with claim 1 and wherein then riding along said longitudinally extending face 25 said tip portion of at least one of said latch members of said one latch member and the innermost one of said transverse faces of said one latch member serving as a stop to limit the pivotal movement of said other latch member and the armature on which it is is a body of a synthetic resinous material having antifriction properties, said body of synthetic resinous material being fixed to a metal strip, said metal strip including a portion extending generally along the mounted. 3O 2. An electromagnetically powered operator in accordance with claim 1 and'wherein said tip portion of at least one of said latch members armature on which said latch member is mounted.

feferences Cited in the file of this patent V UNITED STATES PATENTS is a body of synthetic resinous material having anti- 1,971,199 Owens Aug 21, 1934 friction properties. 35 2,756,612 chleicher July 31, 1956 3. An electromagnetically powered operator in accord 2,819,364 iaidinger I an. 7, 1958 ance with claim 2 and wherein 1 2,825,239 Lauterer Mar. 4, 1958 

1. IN AN ELECTROMAGNETICALLY POWERED OPERATOR OF THE TYPE COMPRISING A SUPPORT; AND TWO ALTERNATELY ENERGIZED MOTOR DEVICES EACH INCLUDING AN ELECTROMAGNET; AN ARMATURE MOUNTED ADJACENT THE ELECTROMAGNET FOR PIVOTAL MOVEMENT, ABOUT AN AXIS TRANSVERSE TO THE AXIS OF THE ELECTROMAGNET, TOWARD AND AWAY FROM ELECTROMAGNET; AND A SPRING CONNECTED TO THE ARMATURE TO BIAS THE SAME AWAY FROM THE ELECTROMAGNET, THE MOTOR DEVICES BEING MOUNTED ON THE SUPPORT IN AT LEAST GENERALLY END-TO-END RELATION WITH THE ARMATURES ADJACENT EACH OTHER AND THE PIVOTAL AXES OF THE ARMATURES IN PARALLEL SPACED RELATION TO EACH OTHER, THE COMBINATION OF A PAIR OF LATCH MEMBERS EACH MOUNTED ON A DIFFERENT ONE OF THE ARMATURES AND EACH EXTENDING GENERALLY ALONG THE LENGTH OF THE ARMATURE ON WHICH IT IS MOUNTED AND AWAY FROM THE PIVOTAL AXIS OF THE ARMATURE, EACH OF SAID LATCH MEMBERS HAVING A TIP PORTION SPACED FROM THE PIVOTAL AXIS OF THE ARMATURE ON WHICH SUCH LATCH MEMBER IS MOUNTED, SAID TIP PORTIONS GENERALLY OPPOSING EACH OTHER ACROSS THE SPACE BETWEEN SAID LATCH MEMBERS, EACH OF SAID TIP PORTIONS COMPRISING A PAIR OF TRANSVERSE FACES EXTENDING PARALLEL TO THE PIVOTAL AXES OF THE ARMATURES AND SPACED APART IN A DIRECTION EXTENDING AT AN OBLIQUE ANGLE TO THE ARMATURE ON WHICH THE LATCH MEMBER IS MOUNTED, THE DIRECTION OF SPACING OF SAID PAIRS OF TRANSVERSE FACES CONVERGING TOWARD EACH OTHER AWAY FROM THE PIVOTAL AXES OF THE ARMATURES, SAID TIP PORTIONS EACH HAVING A LONGITUDINALLY EXTENDING FACE INTERCONNECTING SAID TRANSVERSE FACES, SAID LONGITUDINALLY EXTENDING FACES OF EACH OF SAID TIP PORTIONS BEING DIRECTED TOWARD THE OTHER OF SAID TIP PORTIONS, THE OUTERMOST ONE OF SAID PAIR OF TRASVERSE FACES OF ONE OF SAID LATCH MEMBERS ENGAGING SAID LONGITUDINALLY EXTENDING FACE OF THE OTHER OF SAID LATCH MEMBERS IN EACH ACTUATED CONDITIONED OF THE OPERATOR, SAID PAIR OF FACES AND SAID LONGITUDINALLY EXTENDING FACE OF AT LEAST ONE OF SAID LATCH MEMBERS BEING OF ANTIFRICTION MATERIAL, ENERGIZATION OF ONE OF THE MOTOR DEVICES CAUSING THE ONE OF SAID LATCH MEMBERS MOUNTED ON THE ARMATURE OF THAT MOTOR DEVICE TO PIVOT AWAY FROM THE OTHER OF SAID LATCH MEMBERS, THE SPRING OF THE OTHER MOTOR DEVICE THEN CAUSING THE ARMATURE THEREOF TO PIVOT TOWARD SAID ONE LATCH MEMBER, THE OUTERMOST ONE OF SAID TRANSVERSE FACES OF SAID OTHER LATCH MEMBER THEN RIDING ALONG SAID LONGITUDINALLY EXTENDING FACE OF SAID ONE LATCH MEMBER AND THE INNERMOST ONE OF SAID TRANSVERSE FACES OF SAID ONE LATCH MEMBER SERVING AS A STOP TO LIMIT THE PIVOTAL MOVEMENT OF SAID OTHER LATCH MEMBER AND THE ARMATURE ON WHICH IT IS MOUNTED. 